Conventionally, as a stopper for closing a container after filling a fluid including various kinds of fluids, such as, e.g., chemicals, cosmetics, drugs and medicines, detergents, foods, beverages, adhesives, paint, and ink and thereafter discharging the fluid filled in the container, a stopper according to Patent Document 1 is known.
The stopper according to Patent Document 1 is equipped with a stopper main body having a guiding path extending in the axial direction and configured to be fixed to an inlet and outlet opening of a container, a first stopper member for filling a fluid in the container, and a second stopper member for closing the guiding path of the stopper main body. A fluid is supplied into the container when the first stopper member is inserted into the guiding path of the stopper main body. The stopper main body is closed by inserting the second stopper member into the guiding path of the stopper main body. A discharge needle is inserted through the second stopper member, so that the fluid filled in the container is discharged to the outside. With this configuration, it becomes possible to easily and reliably perform a series of operations of filling the fluid, closing the container, and discharging the fluid while preventing possible leakage of fluid and/or inclusion of air.
By the way, in such a stopper, it is extremely important how the stopper member (second stopper member) locks the sealing member, and various proposals have been made on the method of locking the sealing member by the stopper member.
For example, the stopper member 2′ shown in FIG. 6(a) has a plurality of peripheral wall sections 27′ divided in the circumferential direction, and both end portions of each peripheral wall section 27′ are fixed to the stopper member. According to this, a sealing member can be easily inserted into the stopper member, which is convenient. However, after inserting the stopper member into which the sealing member is inserted into the stopper main body, when the discharge needle is inserted through the sealing member and then pulled out of the sealing member, there is a possibility that the sealing member comes off from the stopper member together with the discharge needle. Of course, if the outer diameter of the sealing member is increased, the sealing member becomes less likely to come off from the stopper member, but this makes it difficult to insert the sealing member into the stopper member.
On the other hand, the stopper member 2′ shown in FIG. 6(b) has a plurality of peripheral wall sections 28′ completely divided in the circumferential direction, and each peripheral wall section 28′ is provided with a protrusion 28b′ protruding radially inward. According to this configuration, when the stopper member is inserted into the stopper main body, the protrusion 28b′ of each peripheral wall section 28′ locks the base end face of a sealing member. This eliminates the possibility that the sealing member comes off from the stopper member. However, in order to insert a sealing member into the stopper member 2′, each peripheral wall section 28′ of the stopper member 2′ had to be opened radially outward. Therefore, it was difficult to insert the sealing member into the stopper member 2′. Further, when inserting a sealing member into the stopper member 2′, if an excessive force is applied to each peripheral wall section 28′, there is a possibility that each peripheral wall section 28′ is deformed, resulting in malfunction thereof.